1
2/*
3 * Copyright 2006 The Android Open Source Project
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10#include "SkColorFilter.h"
11#include "SkShader.h"
12#include "SkUnPreMultiply.h"
13
14bool SkColorFilter::asColorMode(SkColor* color, SkXfermode::Mode* mode) {
15    return false;
16}
17
18bool SkColorFilter::asColorMatrix(SkScalar matrix[20]) {
19    return false;
20}
21
22bool SkColorFilter::asComponentTable(SkBitmap*) {
23    return false;
24}
25
26void SkColorFilter::filterSpan16(const uint16_t s[], int count, uint16_t d[]) {
27    SkASSERT(this->getFlags() & SkColorFilter::kHasFilter16_Flag);
28    SkDEBUGFAIL("missing implementation of SkColorFilter::filterSpan16");
29
30    if (d != s) {
31        memcpy(d, s, count * sizeof(uint16_t));
32    }
33}
34
35SkColor SkColorFilter::filterColor(SkColor c) {
36    SkPMColor dst, src = SkPreMultiplyColor(c);
37    this->filterSpan(&src, 1, &dst);
38    return SkUnPreMultiply::PMColorToColor(dst);
39}
40
41///////////////////////////////////////////////////////////////////////////////
42
43SkFilterShader::SkFilterShader(SkShader* shader, SkColorFilter* filter) {
44    fShader = shader;   shader->ref();
45    fFilter = filter;   filter->ref();
46}
47
48SkFilterShader::SkFilterShader(SkFlattenableReadBuffer& buffer) :
49        INHERITED(buffer) {
50    fShader = static_cast<SkShader*>(buffer.readFlattenable());
51    fFilter = static_cast<SkColorFilter*>(buffer.readFlattenable());
52}
53
54SkFilterShader::~SkFilterShader() {
55    fFilter->unref();
56    fShader->unref();
57}
58
59void SkFilterShader::beginSession() {
60    this->INHERITED::beginSession();
61    fShader->beginSession();
62}
63
64void SkFilterShader::endSession() {
65    fShader->endSession();
66    this->INHERITED::endSession();
67}
68
69void SkFilterShader::flatten(SkFlattenableWriteBuffer& buffer) {
70    this->INHERITED::flatten(buffer);
71    buffer.writeFlattenable(fShader);
72    buffer.writeFlattenable(fFilter);
73}
74
75uint32_t SkFilterShader::getFlags() {
76    uint32_t shaderF = fShader->getFlags();
77    uint32_t filterF = fFilter->getFlags();
78
79    // if the filter doesn't support 16bit, clear the matching bit in the shader
80    if (!(filterF & SkColorFilter::kHasFilter16_Flag)) {
81        shaderF &= ~SkShader::kHasSpan16_Flag;
82    }
83    // if the filter might change alpha, clear the opaque flag in the shader
84    if (!(filterF & SkColorFilter::kAlphaUnchanged_Flag)) {
85        shaderF &= ~(SkShader::kOpaqueAlpha_Flag | SkShader::kHasSpan16_Flag);
86    }
87    return shaderF;
88}
89
90bool SkFilterShader::setContext(const SkBitmap& device,
91                                const SkPaint& paint,
92                                const SkMatrix& matrix) {
93    return  this->INHERITED::setContext(device, paint, matrix) &&
94            fShader->setContext(device, paint, matrix);
95}
96
97void SkFilterShader::shadeSpan(int x, int y, SkPMColor result[], int count) {
98    fShader->shadeSpan(x, y, result, count);
99    fFilter->filterSpan(result, count, result);
100}
101
102void SkFilterShader::shadeSpan16(int x, int y, uint16_t result[], int count) {
103    SkASSERT(fShader->getFlags() & SkShader::kHasSpan16_Flag);
104    SkASSERT(fFilter->getFlags() & SkColorFilter::kHasFilter16_Flag);
105
106    fShader->shadeSpan16(x, y, result, count);
107    fFilter->filterSpan16(result, count, result);
108}
109
110